Metropolitan Kallistos of Diokleia, formerly Timothy Ware, is unquestionably the best-known Orthodox theologian in the Western world today. The papers collected in this volume are designed to demonstrate the spread of his own interests and concerns and therefore range from the Desert Fathers to modern church dialogue, from patristics to church music, from the Philokalia to human «priesthood». In the course of a long career he has touched the lives of many people and there is a section of tributes concerned with his role as spiritual father, teacher, writer, pastor, theologian, and monk. In the epilogue the Metropolitan himself reflects on his many years as a pilgrim to Mount Athos. Most of the papers included in this volume were delivered at a conference convened by the Friends of Mount Athos at Madingley Hall, Cambridge, in 2015 in honour of Metropolitan Kallistos's eightieth birthday.